1. Field of the Invention
The invention lies in the field of conveying technology and relates to an apparatus and a method by means of which a conveying stream of flexible flat articles, in particular printed products, is shifted. Shifting is understood to mean the position of the articles, or at least one of the edges thereof, being changed relative to the conveying direction of the conveying stream.
2. Description of Related Art
In printing technology, but also in other fields, articles, e.g. printed products, are often conveyed in a conveying stream continuously one behind the other between various processing stations. The position of the articles in relation to the conveying direction and/or the orientation in space upon leaving a first processing station in this case frequently does not correspond to the position which is necessary for further processing. For example, printed products often leave a folding station in a product stream in which the folded edges are oriented in the conveying direction and in which the products are upright. For further processing, however, it is desirable to have a product stream in which the folded edges are oriented transversely to the conveying direction and in which the products are lying down. In order to achieve this shifting, use is made, for example, of intermediate conveyors which, in the first instance, set down the upright product stream, i.e. rotate it through 90° about an axis running in the conveying direction. Then, the articles are set down in a separated state on a conveying belt running transversely to the original conveying direction. This is described, for example, in U.S. Pat. No. 7,458,926 or in Swiss Patent Application No. 1209/09, which was not published before the priority date.
CH 617 408, EP-B 1375 404 or EP-B 1 318 095 discloses apparatuses by means of which the conveying direction of an imbricated formation of printed products which is conveyed in a lying-down state can be rotated through 90°, while maintaining the horizontal conveying plane. For this purpose, the articles are conveyed against a stop, as a result of which the movement in the original conveying direction of these articles is stopped. In the region of the stop, the articles are subjected to the influence of a removal conveyor, which conveys transversely to the original conveying direction. Therefore, the product stream, deflected through 90°, will maintain the imbricated formation. The orientation of a predetermined product edge, however, changes relative to the conveying direction. Since the imbricated formation has not broken up in the meantime, the possible uses of such apparatuses are limited. In particular it is not possible for any imbricated stream of products folded one inside the other to be converted into an imbricated stream of products located one on top of the other.
EP-A 0 900 757 discloses a deflecting apparatus by means of which a stream of individually conveyed printed products which leave the exit of a folding former individually in the vertical direction is converted into an imbricated stream conveyed in the horizontal direction. There is no change here, however, in the orientation of the folded edge relative to the conveying direction. This apparatus is not suitable, in particular, for folding installations which fold an imbricated stream which is conveyed in a folding direction.
The disadvantage with the known shifting apparatuses and methods in which it is intended to change the product position in space and the orientation of a certain edge relative to the conveying direction is that a comparatively large amount of space is required. The installation according to U.S. Pat. No. 7,458,926 or Swiss Patent Application No. 1209/09 requires a distance of 1 to 1.5 m, for example, in order for the product stream, which is conveyed in an upright state in the first instance, to be set down laterally.
More compact installations provide for the formation of intermediate stacks. The intermediate stacks are broken up in a suitable manner, and therefore the articles in the resulting conveying stream have the appropriate orientation. However, the articles here have to be fully braked and accelerated again. Continuous processing is not possible.